Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual é o número de tentativas contra, quando a diferença de tentativas é +15?
 ###Tabelas: CREATE TABLE alloys_for_mechanical_composition (alloys_for_mechanical_composition_id AUTO_INCREMENT PRIMARY KEY, Sn/Sb (%) VARCHAR, Liquidat (°C) INT, Solidat (°C) INT, Hardness ( Brinell ) INT, Purpose VARCHAR) CREATE TABLE pool_2 (pool_2_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, Tries for VARCHAR, Tries against VARCHAR, Try diff VARCHAR, Points for VARCHAR, Points against VARCHAR, Points diff VARCHAR) CREATE TABLE popular_languages_used_for_data_exchange (popular_languages_used_for_data_exchange_id AUTO_INCREMENT PRIMARY KEY, Schemas VARCHAR, Flexible VARCHAR, Semantic verification VARCHAR, Dictionary VARCHAR, Information Model VARCHAR, Synonyms and homonyms VARCHAR, Dialecting VARCHAR, Web standard VARCHAR, Transformations VARCHAR, Lightweight VARCHAR, Human readable VARCHAR) CREATE TABLE summaries (summaries_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, Manager VARCHAR, Home city VARCHAR, Stadium VARCHAR, Capacity INT) CREATE TABLE parliamentary_parties (parliamentary_parties_id AUTO_INCREMENT PRIMARY KEY, Abbr. VARCHAR, Political Leader VARCHAR, International Affiliation VARCHAR, Votes ( 2012 ) VARCHAR, House of Rep. seats INT, Senate seats INT, European Parliament seats INT)  
SELECT Tries against FROM pool_2 WHERE Try diff = +15